Backend Patterns

Use this skill when building backend features. Follow these patterns for consistency.

Project Setup

Replace these placeholders for your project:

• @project/ → your package scope (e.g., @myapp/)
• packages/ paths follow standard monorepo layout

Expected packages:

• @project/db - Drizzle database client, DB_SCHEMA export
• @project/shared - TypeIDs, constants, shared schemas
• @project/logger - Pino logger wrapper

Quick Reference

Entity Type	Pattern	Files to Create/Modify
Service	Factory function with deps, neverthrow	packages/api/src/services/xxx-service.ts, context.ts
Schema	3-file pattern	.db.ts, .zod.ts, .relations.ts in packages/db/src/schema/
Router	ORPC procedures, Result→Error mapping	packages/api/src/routers/xxx-router.ts, routers.ts
TypeID	Prefixed ID	packages/shared/src/typeid.schema.ts

Key Conventions

• db.query preferred over db.select for simple lookups (see service.md)
• neverthrow for service error handling, .match() in routers (see router.md)
• Zod enums with as const + z.enum() pattern (see schema.md)

Pattern Details

• For service creation, see service.md
• For schema creation, see schema.md
• For router creation, see router.md

Workflow: Adding a New Entity

1. Add TypeID prefix to packages/shared/src/typeid.schema.ts
2. Create schema files in packages/db/src/schema/{domain}/
3. Create service in packages/api/src/services/
4. Add to context in packages/api/src/context.ts
5. Create router in packages/api/src/routers/
6. Export router in packages/api/src/routers/routers.ts
7. Run bun run db:generate if schema changed